Cyclical patterns in volcanic degassing revealed by SO2 flux timeseries analysis: An application to Soufrière Hills Volcano, Montserrat

Abstract

Here,usingalongSO2 timeseries fromSHV,withcontinuousmeasurementssince2002, we explore for the first time degassing behaviour at aresolution comparable to that possible for seismic and deformation datasets. Timeseries analysis of flux data spanning 2002–2011revealsthatSO2 emissions at SHV exhibit complex cyclicity, with dominant cycles evident on both multi-year and multi-week ( 50 day)timescales.These cycles persist through phases of both active extrusion and eruptive pause, and show close similarities to periodic components previously identified at SHVin time series of seismicity, ground deformation and lava extrusion.